Form feeding control device

Abstract

A form feeding control device includes a sensor provided at an inlet mouth of a printer to sense whether or not a continuous form exists in the inlet mouth. A control unit feeds the continuous for transfer thereto of a printed image corresponding to one page of the continuous form. The printed image is then fixed on the continuous form. The control unit also feeds the continuous form to fix the printed image on one page when the sensor senses that the end of the continuous form has passed through the inlet mouth and that a printed image has been transferred to the continuous form.

We claim: 
     
       1. A device for controlling the feeding of a continuous form provided in a printer, said device comprising: means for feeding the continuous form;   means for sensing the existence of the continuous form in an inlet mouth through which the continuous form is supplied;   a transfer unit for transferring a printed image by an electrophotographing process to the continuous form fed by said feeding means;   a fixing unit for fixing said printed image transferred by said transfer unit onto the continuous form;   first control means for controlling said transfer unit to transfer a printed image to a first page of the continuous form when printing data corresponding to said first page is accumulated, controlling said fixing unit to fix said printing image to said first page of said continuous form, and controlling said transfer unit to transfer a printed image to a second page of the continuous form following said first page when printing data corresponding to said second page is accumulated; and   second control means for controlling said fixing unit to fix a page of the continuous form to which a printed image has been transferred, when said sensing means senses that .[.said.]. .Iadd.the .Iaddend.continuous form does not exist .[.is.]. .Iadd.in .Iaddend.said inlet mouth.   
     
     
       2. A device according to claim 1, wherein said feeding means comprises a pair of rollers for feeding the continuous form, and a tractor unit provided upstream of said pair of rollers and imposing a rearward tension on the continuous form. 
     
     
       3. A device according to claim 2, wherein said tractor unit is provided with a means for outputting pulse signals in accordance with a feed amount of the continuous form. 
     
     
       4. A device according to claim 3, wherein said feeding means controls the feed amount of the continuous form in accordance with said pulse signals, and when said sensing means senses that the continuous form does not exist in said inlet mouth, feeds one page of the continuous form in accordance with a larger number of said pulse signals than the number of pulse signals usually used for feeding one page. 
     
     
       5. A device according to claim 1, wherein said sensing means outputs a signal when an end of the continuous form has passed through said inlet mouth. 
     
     
       6. A device according to claim 1, wherein said transfer unit and said fixing unit are separated by a distance equivalent to one page of the continuous form. 
     
     
       7. A device for controlling a feeding of a continuous form provided in a printer, said device comprising; means for sensing .[.and.]. .Iadd.an .Iaddend.existence of the continuous form which has not been printed, said sensing means being provided at an inlet mouth through which the continuous form is supplied;   a transfer unit for transferring a printed image by an electrophotographing process to the continuous form fed from said inlet mouth;   a fixing unit for fixing said printed image transferred by said transfer unit onto the continuous form;   first control means for controlling said transfer unit to transfer a printed image to a first page of the continuous form when printing data corresponding to said first page is accumulated, controlling said fixing unit to fix said printed image to said first page of the continuous form, and controlling said transfer unit to transfer a printed image to a second page of the continuous form following said first page when printing data corresponding to said second page is accumulated; and   second control means for controlling said fixing unit to fix a page of the continuous form to which a printed image has been transferred, when .Iadd.said .Iaddend.sensing means senses that the continuous form does not .[.exits.]. .Iadd.exist .Iaddend.in said inlet mouth.   
     
     
       8. A device for controlling a feeding of a continuous form provided in a printer, said device comprising; means for sensing an existence of the continuous .[.from.]. .Iadd.form .Iaddend.which has not been printed, said sensing means being provided at an inlet mouth through which the continuous form is supplied;   a transfer unit for transferring a printed image by an electrophotographing process to the continuous form fed from said inlet mouth, said transfer unit transferring a printed image to one page of the continuous form when printing data corresponding to said one page is accumulated; and   a fixing unit for fixing said printed image transferred by said transfer unit to said one page of the continuous form, when printing data corresponding to a next page of the continuous form is accumulated, and when said sensing means senses that the continuous form does not .[.exits.]. .Iadd.exist .Iaddend.in said inlet mouth. .Iadd.9. A device for controlling feeding of a continuous form provided in a printer, said device comprising:   means for feeding the continuous form;   means for sensing an existence of the continuous form in an inlet mouth through which the continuous form is supplied;   means for forming a printed image by an electrophotographing process on the continuous form fed by said feeding means;   a fixing unit for fixing said printed image formed by said forming means onto the continuous form;   
     
     
       first control means for controlling said forming means to form a printed image on a first page of the continuous form after printing data corresponding to said first page is accumulated, controlling said fixing unit to fix said printing image to said first page of the continuous form, and controlling said forming means to form a printed image on a second page of the continous form following said first page after printing data corresponding to said second page is accumulated; and second control means for controlling said fixing unit to fix a page of the continuous form on which a printed image has been formed, when said sensing means senses that the continuous form does not exist in said inlet mouth. .Iaddend. .Iadd.10. A device according to claim 9, wherein said means for forming a printed image includes a transfer unit for transferring a printed image to the continuous form. .Iaddend. .Iadd.11. A printer for printing on a continuous form, said printer comprising:   means for sensing an abnormal state of the printer;   means for feeding the continuous form by at least one page in a direction in which the continuous form is discharged, when said sensing means senses that said abnormal state of the printer exists; and   means for applying toner to the continuous form, wherein said abnormal state is an error relating to the toner. .Iaddend. .Iadd.12. A printer according to claim 11, wherein said feeding means feeds the continous form by an amount which is larger than a predetermined amount corresponding to one page, when said sensing means senses said abnormal state of the printer. .Iaddend. .Iadd.13. A printer for printing on a continous form, said printer comprising:   means for sensing an abnormal state of the printer;   means for feeding the continuous form by at least one page in a direction in which the continuous form is discharged, when said sensing means senses that said abnormal state of the printer exists; and   wherein said feeding means comprises a pair of rollers for feeding the continuous form, and a tractor unit provided upstream of said pair of rollers and imposing a rearward tension on the continuous form, said tractor unit being provided with means for outputting pulse signals in accordance with the amount of continuous form which is fed. .Iaddend. .Iadd.14. A printer according to claim 13, wherein said abnormal state occurs when the continuous form in the printer is exhausted. .Iaddend. .Iadd.15. A printer according to claim 13, wherein said feeding means controls the amount of the continuous form fed in accordance with said pulse signals, and when said sensing means senses that the continuous form does not exist in an inlet mouth of the printer, feeds one page of the continuous form in accordance with a larger number of said pulse signals than the number of pulse signals usually used for feeding one page. .Iaddend. .Iadd.16. A printer for printing on a continuous form, said printer comprising:   means for sensing an abnormal state of the printer;   means for feeding the continuous form by at least one page in a direction in which the continuous form is discharged, when said sensing means senses that said abnormal state of the printer exists; and   wherein said sensing means outputs a signal when an end of the continuous form has passed through said inlet mouth.Iaddend.. .Iadd.17. A printer for printing on a continuous form, said printer comprising:   means for sensing an abnormal state of the printer;   means for feeding the continuous form by at least one page in a direction in which the continuous form is discharged, when said sensing means senses that said abnormal state of the printer exists; and   means for displaying the type of sensed abnormal state, wherein said means for displaying prints an indication of said abnormal state on said at least one page. .Iaddend. .Iadd.18. A printer for printing on a continuous form, said printer comprising:   means for sensing an abnormal state of the printer;   means for feeding the continous form by at least one page in a direction in which the continuous form is discharged, and then stopping the feeding operation, when said sensing means senses that said abnormal state of the printer exists.